Delay of adequate empiric antibiotic therapy is associated with increased mortality among solid-organ transplant patients

Initial empirical antibiotic therapy in kidney transplant recipients with pyelonephritis: A global survey of current practice and opinions across 19 countries on six continents

BACKGROUND

Despite the burden of pyelonephritis after kidney transplantation, there is no consensus on initial empirical antibiotic management.

METHODS

We surveyed clinicians throughout the world on their practice and opinions about the initial empirical therapy of post-transplant pyelonephritis, using clinical vignettes. A panel of experts from 19 countries on six continents designed this survey, and invited 2145 clinicians to participate.

RESULTS

A total of 721 clinicians completed the survey (response rate: 34%). In the hypothetical case of a kidney transplant recipient admitted with pyelonephritis but not requiring intensive care, most respondents reported initiating either a 3rd-generation cephalosporin (37%) or piperacillin-tazobactam (21%) monotherapy. Several patient-level factors dictated the selection of broader-spectrum antibiotics, including having a recent urine culture showing growth of a resistant organism (85% for extended-spectrum ß-lactamase-producing organisms, 90% for carbapenemase-producing organisms, and 94% for Pseudomonas aeruginosa). Respondents attributed high importance to the appropriateness of empirical therapy, which 87% judged important to prevent mortality. Significant practice and opinion variations were observed between and within countries.

CONCLUSION

High-quality studies are needed to guide the empirical management of post-transplant pyelonephritis. In particular, whether prior urine culture results should systematically be reviewed and considered remains to be determined. Studies are also needed to clarify the relationship between the appropriateness of initial empirical therapy and outcomes of post-transplant pyelonephritis.

Diagnosing and Managing Urinary Tract Infections in Kidney Transplant Recipients

In the article, the authors review antibiotic treatment options for both acute uncomplicated UTI and complicated UTI. In addition, they review alternative regimens which are needed in the setting of drug-resistant pathogens including vancomycin-resistant Enterococcus, -extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E), carbapenem-resistant Enterobacterales, and carbapenem-resistant Pseudomonas, which are encountered with more frequency.

Validation of risk scores for prediction of severe pneumonia in kidney transplant recipients hospitalized with community-acquired pneumonia

PURPOSE

Risk scores for community-acquired pneumonia (CAP) are widely used for standardized assessment in immunocompetent patients and to identify patients at risk for severe pneumonia and death. In immunocompromised patients, the prognostic value of pneumonia-specific risk scores seems to be reduced, but evidence is limited. The value of different pneumonia risk scores in kidney transplant recipients (KTR) is not known.

METHODS

Therefore, we retrospectively analyzed 310 first CAP episodes after kidney transplantation in 310 KTR. We assessed clinical outcomes and validated eight different risk scores (CRB-65, CURB-65, DS-CRB-65, qSOFA, SOFA, PSI, IDSA/ATS minor criteria, NEWS-2) for the prognosis of severe pneumonia and in-hospital mortality. Risk scores were assessed up to 48 h after admission, but always before an endpoint occurred. Multiple imputation was performed to handle missing values.

RESULTS

In total, 16 out of 310 patients (5.2%) died, and 48 (15.5%) developed severe pneumonia. Based on ROC analysis, sequential organ failure assessment (SOFA) and national early warning score 2 (NEWS-2) performed best, predicting severe pneumonia with AUC of 0.823 (0.747-0.880) and 0.784 (0.691-0.855), respectively.

CONCLUSION

SOFA and NEWS-2 are best suited to identify KTR at risk for the development of severe CAP. In contrast to immunocompetent patients, CRB-65 should not be used to guide outpatient treatment in KTR, since there is a 7% risk for the development of severe pneumonia even in patients with a score of zero.

Infections in Heart and Lung Transplant Recipients

Infections in heart and lung transplant recipients are complex and heterogeneous. This article reviews the epidemiology, risk factors, specific clinical syndromes, and most frequent opportunistic infections in heart and/or lung transplant recipients that will be encountered in the intensive care unit and will provide a practical approach of empirical management.

Multidrug-Resistant Sepsis: A Critical Healthcare Challenge

Sepsis globally accounts for an alarming annual toll of 48.9 million cases, resulting in 11 million deaths, and inflicts an economic burden of approximately USD 38 billion on the United States healthcare system. The rise of multidrug-resistant organisms (MDROs) has elevated the urgency surrounding the management of multidrug-resistant (MDR) sepsis, evolving into a critical global health concern. This review aims to provide a comprehensive overview of the current epidemiology of (MDR) sepsis and its associated healthcare challenges, particularly in critically ill hospitalized patients. Highlighted findings demonstrated the complex nature of (MDR) sepsis pathophysiology and the resulting immune responses, which significantly hinder sepsis treatment. Studies also revealed that aging, antibiotic overuse or abuse, inadequate empiric antibiotic therapy, and underlying comorbidities contribute significantly to recurrent sepsis, thereby leading to septic shock, multi-organ failure, and ultimately immune paralysis, which all contribute to high mortality rates among sepsis patients. Moreover, studies confirmed a correlation between elevated readmission rates and an increased risk of cognitive and organ dysfunction among sepsis patients, amplifying hospital-associated costs. To mitigate the impact of sepsis burden, researchers have directed their efforts towards innovative diagnostic methods like point-of-care testing (POCT) devices for rapid, accurate, and particularly bedside detection of sepsis; however, these methods are currently limited to detecting only a few resistance biomarkers, thus warranting further exploration. Numerous interventions have also been introduced to treat MDR sepsis, including combination therapy with antibiotics from two different classes and precision therapy, which involves personalized treatment strategies tailored to individual needs. Finally, addressing MDR-associated healthcare challenges at regional levels based on local pathogen resistance patterns emerges as a critical strategy for effective sepsis treatment and minimizing adverse effects.

Risk Factors and Outcomes of Acute Graft Pyelonephritis with Bacteremia Due to Multidrug-Resistant Gram-Negative Bacilli among Kidney Transplant Recipients

Acute graft pyelonephritis (AGP) is the leading cause of bloodstream infection in kidney transplant (KT) recipients. The prevalence of urinary tract infections caused by multidrug-resistant (MDR) Gram-negative bacilli is increasing. This 14-year prospective observational study sought to determine the clinical characteristics, risk factors, and outcomes of AGP with bacteremia due to MDR Gram-negative bacilli. Overall, 278 episodes of AGP with bacteremia due to MDR Gram-negative and non-MDR Gram-negative bacilli were identified and compared in 214 KT recipients; MDR Gram-negative bacilli were the cause in 28.4%. Overall 30-day mortality was low (1.1%). Risk factors independently associated with AGP due to MDR Gram-negative bacilli were male sex (OR 3.08; 95%CI 1.60–5.93), previous episode of bacteremic AGP (OR 2.11, 95%CI 1.09–4.09), prior antibiotic therapy in the preceding month (OR 2.47, 95%CI 1.33–4.57), and nosocomial acquisition (OR 2.03, 95%CI 1.14–3.62). Forty-three percent of MDR Gram-negative episodes received inappropriate empirical antibiotic therapy. The risk factors identified in this study may help physicians when selecting empirical antibiotic treatment for AGP. Previous antibiotic use was the main modifiable factor. Its presence highlights the importance of avoiding unnecessary antibiotics in order to bring down the high rates of MDR Gram-negative bacilli infections in this population.

White paper on antimicrobial stewardship in solid organ transplant recipients

Antimicrobial stewardship programs (ASPs) have made immense strides in optimizing antibiotic, antifungal, and antiviral use in clinical settings. However, although ASPs are required institutionally by regulatory agencies in the United States and Canada, they are not mandated for transplant centers or programs specifically. Despite the fact that solid organ transplant recipients in particular are at increased risk of infections from multidrug-resistant organisms, due to host and donor factors and immunosuppressive therapy, there currently are little rigorous data regarding stewardship practices in solid organ transplant populations, and thus, no transplant-specific requirements currently exist. Further complicating matters, transplant patients have a wide range of variability regarding their susceptibility to infection, as factors such as surgery of transplant, intensity of immunosuppression, and presence of drains or catheters in situ may modify the risk of infection. As such, it is not feasible to have a "one-size-fits-all" style of stewardship for this patient population. The objective of this white paper is to identify opportunities, risk factors, and ASP strategies that should be assessed with solid organ transplant recipients to optimize antimicrobial use, while producing an overall improvement in patient outcomes. We hope it may serve as a springboard for development of future guidance and identification of research opportunities.

Multidrug-resistant organisms: A significant cause of severe sepsis in pediatric intestinal and multi-visceral transplantation

Severe sepsis in immunocompromised children is associated with increased mortality. This paper describes the epidemiology landscape, clinical acuity, and outcomes for severe sepsis in pediatric intestinal (ITx) and multi-visceral (MVTx) transplant recipients requiring admission to the pediatric intensive care unit (PICU). Severe sepsis episodes were retrospectively reviewed in 51 ITx and MVTx patients receiving organs between 2009 and 2015. Twenty-nine (56.8%) patients had at least one sepsis episode (total of 63 episodes) through December 2016. Bacterial etiologies accounted for 66.7% of all episodes (n = 42), occurring a median of 122.5 days following transplant (IQR 59-211.8 days). Multidrug-resistant organisms (MDROs) accounted for 73.8% of bacterial infections; extended spectrum beta-lactamase producers, vancomycin-resistant enterococcus, and highly-resistant Pseudomonas aeruginosa were the most commonly identified. Increased mechanical ventilation and vasoactive requirements were noted in MDRO episodes (OR 3.03, 95% CI 1.09-8.46 and OR 3.07, 95% CI 1.09-8.61, respectively; p < .05) compared to non-MDRO episodes. PICU length of stay was significantly increased for MDRO episodes (7 vs. 3 days, p = .02). Graft loss was 24.1% (n = 7) and mortality was 24.1% (n = 7) in patients who experienced severe sepsis. Further attention is needed for MDRO risk mitigation and modification of sepsis treatment guidelines to ensure MDRO coverage for this population.

Evidence for the Application of Sepsis Bundles in 2021

Sepsis represents a severe condition that predisposes patients to a high risk of death if its progression is not ended. As with other time-dependent conditions, the performance of determinant interventions has led to significant survival benefits and quality-of-care improvements in acute emergency care. Thus, the initial interventions in sepsis are a cornerstone for prognosis in most patients. Even though the evidence supporting the hour-1 bundle is perfectible, real-life application of thoughtful and organized sepsis care has improved survival and quality of care in settings promoting compliance to evidence-based treatments. Current evidence for implementing the Surviving Sepsis Campaign bundles for early sepsis management is moving forward to better approaches as more substantial evidence evolves.

The time is now: antimicrobial stewardship in solid organ transplantation

PURPOSE OF REVIEW

To provide a summary of complications of antimicrobials and opportunities for antimicrobial stewardship (AS) in solid organ transplant (SOT) patient care.

RECENT FINDINGS

Personalized, precision antimicrobial prescribing in SOT aiming to avoid negative consequences of antimicrobials is essential to improving patient outcomes. The positive impact AS efforts in transplant care has been recognized and bespoke activities tailored to special interests of transplant patients and providers are evolving. Strategies to optimize stewardship interventions targeting antibacterial, antiviral, and antifungal drug selection and dosing in the transplant population have been recently published though clinical integration using a 'handshake' stewardship model is an optimal starting point in transplant care. Other recent studies involving transplant recipients have identified opportunities to shorten duration or avoid antimicrobials for certain commonly encountered clinical syndromes. This literature, informing recent consensus clinical practice guidelines, may help support institutional practice guidelines and protocols. Proposals to track and report stewardship process and outcome measures as a routine facet of programmatic transplant quality reporting have been published. However, developing novel metrics accounting for nuances of transplant patients and programs is critical. Important studies are needed to evaluate organizational transplant prescribing cultures and optimal behavioral science-based interventions relevant to antimicrobial use in this population.

SUMMARY

Consequences of antimicrobial use, such as drug toxicities, and Clostridiodes difficile (CDI) and multidrug-resistant organisms colonization and infection disproportionately affect SOT recipients and are associated with poor allograft and patient outcomes. Stewardship programs encompassing transplant patients aim to personalize antimicrobial prescribing and optimize outcomes. Further studies are needed to better understand optimal intervention strategies in SOT.

Asymptomatic bacteriuria and urinary tract infections in kidney transplant recipients

PURPOSE OF REVIEW

Urinary tract infection (UTI) is the most common infection in kidney transplant recipients (KTRs). Several elements increase the risk of UTI and/or modify its clinical presentation among KTRs (e.g. immunosuppressive therapy, kidney allograft denervation, and use of urinary catheters). Also, KTRs may have UTIs because of difficult-to-identify and/or difficult-to-treat organisms. We provide an overview of the current knowledge regarding bacterial UTIs in KTRs, with a focus on recent findings.

RECENT FINDINGS

There is accumulating evidence from clinical trials that screening for and treating asymptomatic bacteriuria is not beneficial in most KTRs (i.e. those who are ≥1-2 months posttransplant and do not have a urinary catheter). These patients have a point-prevalence of asymptomatic bacteriuria of only 3% and treating asymptomatic bacteriuria probably does not improve their outcomes. There is no clinical trial evidence to guide the management of symptomatic UTI in KTRs. Several important clinical questions remain unanswered, especially regarding the management of posttransplant pyelonephritis and the prevention of UTI in KTRs.

SUMMARY

Despite its frequency and associated morbidity, UTI after kidney transplantation is an understudied infection. In an era of increasing antimicrobial resistance and limited resources, further research is needed to ensure optimal use of antimicrobials in KTRs with UTI.

Solid organ transplant-specific antibiogram in a tertiary pediatric hospital in Canada

SOT recipients are more vulnerable to infections with antimicrobial-resistant organisms, and therefore, it may be useful for transplant centers to create transplant-specific antibiograms to direct empirical antimicrobial regimens and monitor trends in antimicrobial resistance. SOT-specific antibiograms were created using antimicrobial susceptibility data on isolates from 2012 to 2018 at The Hospital for Sick Children, Toronto, Ontario, Canada. The CLSI guidelines were followed to generate the antibiograms except that results from 2 years of data were pooled on a rolling basis to achieve larger sample sizes. The 3 most frequent organisms in one analysis period of the SOT antibiogram were Escherichia coli (average sample size ±standard deviation; n = 28.7 ± 3.8), Staphylococcus aureus (n = 27.8 ± 5.0), and Pseudomonas aeruginosa (non-CF) (n = 19.8 ± 8.8). For E.coli, susceptibilities in the SOT antibiogram were significantly lower than those in the hospital-wide antibiogram in 2017-2018 for ampicillin (27% vs 47%; p = .014), piperacillin/tazobactam (55% vs 88%; p < .001), cefotaxime (59% vs 89%; p < .001), ciprofloxacin (71% vs 88%; p = .007), and trimethoprim-sulfamethoxazole (41% vs 69%; p = .001), but not significantly different for aminoglycosides and meropenem. In the SOT antibiogram of E. coli, decreased susceptibility trend was confirmed in some antibiotics, including piperacillin/tazobactam (83% in 2012-2013 vs 55% in 2017-2018). At our center, the solid organ transplant-specific antibiogram revealed important differences in E. coli susceptibilities and trends in antimicrobial resistance. Developing a SOT antibiogram will assist in revising and improving empiric treatment guidelines as well as monitoring antimicrobial resistance in this population.

Early Bacterial Infections After Pediatric Liver Transplantation in the Era of Multidrug-resistant Bacteria: Nine-year Single-center Retrospective Experience

BACKGROUND

Early bacterial infection is a major and severe complication after liver transplantation (LT). The rise of antimicrobial resistance, especially extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE), is a growing concern for these patients. This study aimed to assess the epidemiology of early bacterial infections in a pediatric population, including those caused by multidrug-resistant (MDR) pathogens, and to identify risk factors for infection.

METHODS

We conducted a monocentric retrospective study including 142 consecutive LTs performed in 137 children between 2009 and 2017.

RESULTS

Ninety-three bacterial infections occurred after 67 (47%) LTs. Among the 82 isolated pathogens, the most common was Klebsiella pneumoniae (n = 19, 23%). Independent risk factors for early bacterial infection were low weight [odds ratio (OR) = 0.96; 95% confidence interval (CI): 0.9-0.99; P = 0.03] and the presence of a prosthetic mesh (OR = 2.4; 95% CI: 1.1-5.4; P = 0.046). Sixty-one children (45%) carried MDR bacteria and 16 infections were caused by MDR pathogens, especially ESBL-producing K. pneumoniae (n = 12). ESBL-PE stool carriage was associated with ESBL-PE infection (OR = 4.5; 95% CI: 1.4-17.4; P = 0.02). Four children died from an infection, three due to ESBL-producing K. pneumoniae.

CONCLUSIONS

This study confirmed a shift toward a predominance of Gram-negative early bacterial infections after pediatric LT. The risk factors for infection were low weight and the presence of a prosthetic mesh. ESBL-PE stool carriage was associated with ESBL-PE infection. Adapted antimicrobial prophylaxis and personalized antibiotherapy are mandatory to reduce infection prevalence and mortality.

Antibiotic treatment in patients with sepsis: a narrative review

Sepsis is a medical emergency and life-threatening condition due to a dysregulated host response to infection, with unacceptably high morbidity and mortality. Similar to acute myocardial infarction or cerebral vascular accident, sepsis is a severe and continuous time-dependent condition. Thus, in the case of sepsis, early and adequate administration of antimicrobials must be a priority, ideally within the first hour of diagnosis, simultaneously with organ support.As a consequence of the emergence of multidrug-resistant pathogens, the choice of antimicrobials should be performed according to the local pathogen patterns of resistance. Individual antimicrobial optimization is essential to achieve adequate concentrations of antimicrobials, to reduce adverse effects, and to ensure successful outcomes, as well as preventing the emergence of multidrug-resistant pathogens. The loading dose is the administration of an initial higher dose of antimicrobials, regardless of the presence of organ dysfunction. Further doses should be implemented according to pharmacokinetics/pharmacodynamics of antimicrobials and should be adjusted according to the presence of renal or liver dysfunction. Extended or continuous infusion of beta-lactams and therapeutic drug monitoring can help to achieve therapeutic levels of antimicrobials. Duration and adequacy of treatment must be reviewed at regular intervals to allow effective de-escalation and administration of short courses of antimicrobials for most patients. Antimicrobial stewardship frameworks, leadership, focus on the optimal duration of treatments, de-escalation, and novel diagnostic stewardship approaches will help us to improve patients the process of care and overall quality of care.

A Systematic Review of the Effect of Delayed Appropriate Antibiotic Treatment on the Outcomes of Patients With Severe Bacterial Infections

BACKGROUND

Patients with severe bacterial infections often experience delay in receiving appropriate treatment. Consolidated evidence of the impact of delayed appropriate treatment is needed to guide treatment and improve outcomes.

RESEARCH QUESTION

What is the impact of delayed appropriate antibacterial therapy on clinical outcomes in patients with severe bacterial infections?

STUDY DESIGN AND METHODS

Literature searches of MEDLINE and Embase, conducted on July 24, 2018, identified studies published after 2007 reporting the impact of delayed appropriate therapy on clinical outcomes for hospitalized adult patients with bacterial infections. Where appropriate, results were pooled and analyzed with delayed therapy modeled three ways: delay vs no delay in receiving appropriate therapy; duration of delay; and inappropriate vs appropriate initial therapy. This article reports meta-analyses on the effect of delay and duration of delay.

RESULTS

The eligibility criteria were met by 145 studies, of which 37 contributed data to analyses of effect of delay. Mortality was significantly lower in patients receiving appropriate therapy without delay compared with those experiencing delay (OR, 0.57; 95% CI, 0.45-0.72). Mortality was also lower in the no-delay group compared with the delay group in subgroups of studies reporting mortality at 20 to 30 days, during ICU stay, or in patients with bacteremia (OR, 0.57 [95% CI, 0.43-0.76]; OR, 0.47 [95% CI, 0.27-0.80]; and OR, 0.54 [95% CI, 0.40-0.75], respectively). No difference was found in time to appropriate therapy between those who died and those who survived (P = .09), but heterogeneity between studies was high.

INTERPRETATION

Avoiding delayed appropriate therapy is essential to reduce mortality in patients with severe bacterial infections.

CLINICAL TRIAL REGISTRATION

PROSPERO; No.: CRD42018104669; URL: www.crd.york.ac.uk/prospero/.

Antimicrobial stewardship in transplant patients

PURPOSE OF REVIEW

To provide an update on the current landscape of antimicrobial stewardship in solid organ transplant (SOT) recipients.

RECENT FINDINGS

Constructing personalized antimicrobial prescribing approaches to avoid untoward consequences of antimicrobials while improving outcomes is an emerging and critical aspect of transplant medicine. Stewardship activities encompassing the specialized interests of transplant patients and programs are evolving. New literature evaluating strategies to optimize antimicrobial agent selection, dosing, and duration have been published. Additionally, consensus guidance for certain infectious clinical syndromes is available and should inform institutional clinical practice guidelines. Novel metrics for stewardship-related outcomes in transplantation are desperately needed. Though exciting new molecular diagnostic technologies will likely be pivotal in the care of immunocompromised patients, optimal clinical adaptation and appropriate integration remains unclear. Important studies understanding the behaviors influencing antimicrobial prescribing in organizational transplant cultures are needed to optimize interventions.

SUMMARY

Consequences of antimicrobial use, such as Clostridiodes difficile and infections with multidrug-resistant organisms disproportionately affect SOT recipients and are associated with poor allograft and patient outcomes. Application of ASP interventions tailored to SOT recipients is recommended though further studies are needed to provide guidance for best practice.

An approach to antibiotic treatment in patients with sepsis

Sepsis is a medical emergency and life-threatening condition due to a dysregulated host response to infection, which is time-dependent and associated with unacceptably high mortality. Thus, when treating suspicious or confirmed cases of sepsis, clinicians must initiate broad-spectrum antimicrobials within the first hour of diagnosis. Optimizing antibiotic use is essential to ensure successful outcomes and to reduce adverse antibiotic effects, as well as preventing drug resistance. All likely pathogens involved should be considered to provide an appropriate antibiotic coverage. Clinicians must investigate on the previous risk of multidrug-resistant (MDR) pathogens, and the principle of individualized dosing should replace the principle of standard dosing. The loading dose is an initial higher dose of an antibiotic for all patients, yet an individualized treatment approach for further doses should be implemented according to pharmacokinetics (PK)/pharmacodynamics (PD) and the presence of renal/liver dysfunction. Extended or continuous infusion of beta-lactams and therapeutic drug monitoring (TDM) can help to achieve therapeutic levels of antimicrobials. Reevaluation of duration and appropriateness of treatment at regular intervals are also necessary. De-escalation and shortened courses of antimicrobials must be considered for most patients, except in some justified circumstances. Leadership, teamwork, antimicrobial stewardship (AS) frameworks, guideline’s recommendations on the optimal duration of treatments, de-escalation, and novel diagnostic stewardship approaches will help us to improve patients’ quality of care.

Antimicrobial stewardship by academic detailing improves antimicrobial prescribing in solid organ transplant patients

We implemented twice-weekly academic detailing rounds in 2015 as an antimicrobial stewardship (AMS) intervention in solid organ transplant (SOT) patients, led by an AMS pharmacist and a transplant infectious diseases physician. They reviewed SOT patients' antimicrobials and made recommendations to prescribers on antimicrobial regimens, diagnostics investigations, and appropriate referrals for transplant infectious diseases consultation. To determine the impact of the intervention, we adjudicated antimicrobials prescriptions using established AMS principles, and compared the proportion of AMS-concordance regimens pre-intervention (2013) with post-intervention (2016) via 4-point-prevalence surveys conducted in each period. All admitted SOT patients who were receiving antimicrobial treatment on survey days were included. Primary outcome was the percentage of antimicrobial regimen adjudicated as AMS concordant. Secondary outcomes were percentage of AMS concordance in patients consulted by transplant infectious diseases; categories of AMS discordance; antimicrobial consumption in defined daily dose/100 patient-days (DDD/100PD); antimicrobial cost in CAD$/PD; and C. difficile infections. Balancing measures were length of stay, 30-day readmission, and in-hospital mortality. We compared outcomes using χ² test or t-test; significant difference was defined as p < 0.05. Pre-intervention surveys included 139 patients, post-intervention, 179 patients, with 62.3% vs. 56.6% receiving antimicrobials, respectively (p = 0.27). AMS concordance increased from 69% (60/87) to 83.7% (93/111), p = 0.01. Not tailoring antimicrobials was the most common discordance category. AMS concordance under transplant infectious diseases was 82.5% (33/40) pre-intervention vs. 76.6% (36/47) post-intervention, p = 0.5. Antimicrobial consumption increased by 15.3% (140.9 vs.162.4 DDD/100PD, p = 0.001). Antimicrobial cost, C. difficile infection rates and balancing measures remained stable. Academic detailing increased appropriate antimicrobial use in SOT patients without untoward effects.

Clinical and economic burden of infections in hospitalized solid organ transplant recipients compared with the general population in Canada - a retrospective cohort study

Infections continue to be a major cause of post-transplant morbidity and mortality, requiring increased health services utilization. Estimates on the magnitude of this impact are relatively unknown. Using national administrative databases, we compared mortality, acute care health services utilization, and costs in solid organ transplant (SOT) recipients to nontransplant patients using a retrospective cohort of hospitalizations in Canada (excluding Manitoba/Quebec) between April-2009 and March-2014, with a diagnosis of pneumonia, urinary tract infection (UTI), or sepsis. Costs were analyzed using multivariable linear regression. We examined 816 324 admissions in total: 408 352 pneumonia; 328 066 UTI's; and 128 275 sepsis. Unadjusted mean costs were greater in SOT compared to non-SOT patients with pneumonia [(C$14 923 ± C$29 147) vs. (C$11 274 ± C$18 284)] and sepsis [(C$23 434 ± C$39 685) vs. (C$20 849 ± C$36 257)]. Mortality (7.6% vs. 12.5%; P < 0.001), long-term care transfer (5.3% vs. 16.5%; P < 0.001), and mean length of stay (11.0 ± 17.7 days vs. 13.1 ± 24.9 days; P < 0.001) were lower in SOT. More SOT patients could be discharged home (63.2% vs. 44.3%; P < 0.001), but required more specialized care (23.5% vs. 16.1%; P < 0.001). Adjusting for age and comorbidities, hospitalization costs for SOT patients were 10% (95% CI: 8-12%) lower compared to non-SOT patients. Increased absolute hospitalization costs for these infections are tempered by lower adjusted costs and favorable clinical outcomes.

Study of Delayed Antibiotic in Pediatric Febrile Immunocompromised Patients and Adverse Events

OBJECTIVES

Bone marrow transplant (BMT) patients or patients receiving chemotherapy for oncologic diagnoses are at risk for sepsis. The association of time to antibiotics (TTA) with outcomes when adjusting for severity of illness has not been evaluated in the pediatric febrile immunocompromised (FI) population. We evaluated the association of TTA with adverse events in a cohort of FI patients presenting to our pediatric emergency department.

METHODS

We performed a retrospective review of consecutive FI patients presenting over a 6.5-year period. Adverse events were defined as intensive care admission within 72 hours of emergency department arrival, laboratory signs of acute kidney injury, inotropic support subsequent to antibiotics, and all-cause mortality within 30 days. Vital signs and interventions were used to define severity of illness. Adjusting for severity of illness at presentation, age, and timing of an institutional intervention designed to reduce TTA in FI patients, we analyzed the association of TTA with individual adverse events as well as with adverse events in aggregate.

RESULTS

We analyzed 1489 patient encounters. In oncology patients, TTA was not associated with the aggregate measure of whether any adverse event subsequently occurred nor with other individual adverse events. For the BMT subpopulation, TTA >60 minutes did show increased odds of intensive care admission within 72 hours as well as for aggregate adverse events.

CONCLUSIONS

Although TTA >60 minutes did show increased odds of aggregate adverse events in the small subgroup of BMT patients, overall TTA was not associated with adverse events in oncology patients as a whole.

Pneumonia in solid organ transplantation: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These guidelines from the AST Infectious Diseases Community of Practice review the diagnosis and management of pneumonia in the post-transplant period. Clinical presentations and differential diagnosis for pneumonia in the solid organ transplant recipient are reviewed. A two-tier approach is proposed based on the net state of immunosuppression and the severity of presentation. With a lower risk of opportunistic, hospital-acquired, or exposure-specific pathogens and a non-severe presentation, empirical therapy may be initiated under close clinical observation. In all other patients, or those not responding to the initial therapy, a more aggressive diagnostic approach including sampling of tissue for microbiological and pathological testing is warranted. Given the broad range of potential pathogens, a microbiological diagnosis is often key for optimal care. Given the limited literature comparatively evaluating diagnostic approaches to pneumonia in the solid organ transplant recipient, much of the proposed diagnostic algorithm reflects clinical experience rather than evidence-based data. It should serve as a template which may be modified according to local needs. The same holds true for the suggested empiric therapies, which need to be adapted to the local resistance patterns. Further study is needed to comparatively evaluate diagnostic and empiric treatment strategies in SOT recipients.

Diagnostic and therapeutic approach to infectious diseases in solid organ transplant recipients

Purpose

Prognosis of solid organ transplant (SOT) recipients has improved, mainly because of better prevention of rejection by immunosuppressive therapies. However, SOT recipients are highly susceptible to conventional and opportunistic infections, which represent a major cause of morbidity, graft dysfunction and mortality.

Methods

Narrative review.

Results

We cover the current epidemiology and main aspects of infections in SOT recipients including risk factors such as postoperative risks and specific risks for different transplant recipients, key points on anti-infective prophylaxis as well as diagnostic and therapeutic approaches. We provide an up-to-date guide for management of the main syndromes that can be encountered in SOT recipients including acute respiratory failure, sepsis or septic shock, and central nervous system infections as well as bacterial infections with multidrug-resistant strains, invasive fungal diseases, viral infections and less common pathogens that may impact this patient population.

Conclusion

We provide state-of the art review of available knowledge of critically ill SOT patients with infections.

Strategies for Antimicrobial Stewardship in Solid Organ Transplant Recipients

Complications of antimicrobial therapy, such as multidrug-resistant organisms and Clostridium difficile, commonly affect solid-organ transplant recipients and have been associated with graft loss and mortality. Although opportunities are abundant, antimicrobial stewardship practices guiding appropriate therapy have been infrequently reported in transplant patients. A patient-centered, multidisciplinary structure, using established antimicrobial optimization principles, is needed to create nuanced approaches to protect patients and antimicrobials and improve outcomes.

Infections in Heart and Lung Transplant Recipients

Infections in heart and lung transplant recipients are complex and heterogeneous. This article reviews the epidemiology, risk factors, specific clinical syndromes, and most frequent opportunistic infections in heart and/or lung transplant recipients that will be encountered in the intensive care unit and will provide a practical approach of empirical management.

Development and Validation of a Model to Predict Growth of Potentially Antibiotic-Resistant Gram-Negative Bacilli in Critically Ill Children With Suspected Infection

Background

Risk-based guidelines aid empiric antibiotic selection for critically ill adults with suspected infection with Gram-negative bacilli with high potential for antibiotic resistance (termed high-risk GNRs). Neither evidence-based guidelines for empiric antibiotic selection nor validated risk factors predicting high-risk GNR growth exist for critically ill children. We developed and validated a model for predicting high-risk GNR growth in critically ill children with suspected infection.

Methods

This is a retrospective cohort study involving 2 pediatric cohorts admitted to a pediatric intensive care unit (ICU) with suspected infection. We developed a risk model predicting growth of high-risk GNRs using multivariable regression analysis in 1 cohort and validated it in a separate cohort.

Results

In our derivation cohort (556 infectious episodes involving 489 patients), we identified the following independent predictors of high-risk GNR growth: hospitalization >48 hours before suspected infection, hospitalization within the past 4 weeks, recent systemic antibiotics, chronic lung disease, residence in a chronic care facility, and prior high-risk GNR growth. The model sensitivity was 96%, the specificity was 48%, performance using the Brier score was good, and the area under the receiver operator characteristic curve (AUROC) was 0.722, indicating good model performance. In our validation cohort (525 episodes in 447 patients), model performance was similar (AUROC, 0.733), indicating stable model performance.

Conclusions

Our model predicting high-risk GNR growth in critically ill children demonstrates the high sensitivity needed for ICU antibiotic decisions, good overall predictive capability, and stable performance in 2 separate cohorts. This model could be used to develop risk-based empiric antibiotic guidelines for the pediatric ICU.

Role of biomarkers in early infectious complications after lung transplantation

Background

Infections and primary graft dysfunction are devastating complications in the immediate postoperative period following lung transplantation. Nowadays, reliable diagnostic tools are not available. Biomarkers could improve early infection diagnosis.

Methods

Multicentre prospective observational study that included all centres authorized to perform lung transplantation in Spain. Lung infection and/or primary graft dysfunction presentation during study period (first postoperative week) was determined. Biomarkers were measured on ICU admission and daily till ICU discharge or for the following 6 consecutive postoperative days.

Results

We included 233 patients. Median PCT levels were significantly lower in patients with no infection than in patients with Infection on all follow up days. PCT levels were similar for PGD grades 1 and 2 and increased significantly in grade 3. CRP levels were similar in all groups, and no significant differences were observed at any study time point. In the absence of PGD grade 3, PCT levels above median (0.50 ng/ml on admission or 1.17 ng/ml on day 1) were significantly associated with more than two- and three-fold increase in the risk of infection (adjusted Odds Ratio 2.37, 95% confidence interval 1.06 to 5.30 and 3.44, 95% confidence interval 1.52 to 7.78, respectively).

Conclusions

In the absence of severe primary graft dysfunction, procalcitonin can be useful in detecting infections during the first postoperative week. PGD grade 3 significantly increases PCT levels and interferes with the capacity of PCT as a marker of infection. PCT was superior to CRP in the diagnosis of infection during the study period.

Solid organ transplant antibiograms: an opportunity for antimicrobial stewardship

OBJECTIVES

We aimed to compare the antimicrobial susceptibility percentages in blood and urine bacterial isolates recovered from solid organ transplant (SOT) recipients with those reported in the hospital-wide antibiogram.

METHODS

Retrospective review of the antimicrobial susceptibilities of bacterial isolates recovered from SOT recipients at a 1550-bed hospital over a 2-year period. Antibiograms were categorized by anatomic site (blood and urine). Percentage of bacterial susceptibilities to specific antibiotics were compared with the hospital-wide antibiogram.

RESULTS

A total of 1889 unique cultures were identified. Blood and urine isolates of Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa had significantly lower susceptibility to first and second line antibiotics compared to the hospital-wide antibiogram.

CONCLUSION

Significant differences in susceptibilities between isolates from blood and urine cultures from SOT recipients and the hospital-wide antibiogram were found. A population-based strategy for the development of antibiograms specific for this group of high-risk patients could better guide appropriate empiric antimicrobial selection.

Clinical and microbiological epidemiology of early and late infectious complications among solid-organ transplant recipients requiring hospitalization

There is limited literature describing the clinical and microbiological characteristics of solid-organ transplant recipients requiring hospitalization for infectious complications. This study reports on the rate and timing of these syndromes and describes the associated microbiological epidemiology. This prevalence cohort study evaluated solid-organ transplant recipients requiring hospitalization during 2007-2011. We reported infectious complications requiring hospitalization in 603 of 1414 readmissions at a rate of 0.43 episodes per 1000 transplant-days (95% CI, 0.40-0.47), with 85% occurring >6 months post-transplantation. The most frequent infectious complications were as follows: respiratory (27%), sepsis or bacteremia (13%), liver or biliary tract (12%), genitourinary (12%), and cytomegalovirus related (9%). Approximately 53% presented without fever, 45% had no pathogen isolated, and multidrug-resistant organisms were isolated in 27% of those with an identified microbiological etiology. Infectious-related complications continue to pose a high clinical burden on our acute care center, with the majority occurring in the late transplant period. Clinicians are faced with the difficult task of prescribing adequate antimicrobial therapy.

Solid organ transplant patients: are there opportunities for antimicrobial stewardship?

OBJECTIVE

Rising incidence of Clostridium difficile and multidrug-resistant organisms' infections and a dwindling development of new antimicrobials are an impetus for antimicrobial stewardship in organ transplant recipients. We sought to understand antimicrobial prescribing practices and identify opportunities for interdisciplinary collaboration among the transplant, antimicrobial stewardship, and infectious diseases teams.

METHODS

In 2013, two assessors conducted four real-time audits on all antimicrobial therapy in transplant patients, assessing each regimen against stewardship principles established by the Centers for Disease Prevention and Control, supplemented by applicable transplant-specific infection guidelines. Chi-square test was used to compare stewardship-concordant and stewardship-discordant audit results relative to transplant infectious diseases consultation.

RESULTS

Analysis was performed on 176 audits. Fifty-eight percent (103/176) received at least one antimicrobial, of which 69.9% (72/103) were stewardship-concordant. Infections were confirmed or suspected in 52.3% (92/176). Of those, 98.9% (91/92) received antimicrobials, and 41.8% (38/91) were prescribed by transplant clinicians. Infectious diseases consultation was associated with more stewardship-concordant prescriptions (78.5% vs. 59.6%, p = 0.03). The most common stewardship-discordant categories were lack of de-escalation, empiric antimicrobial spectrum being too broad, and therapy duration being too long.

CONCLUSIONS

Opportunities exist for antimicrobial stewardship in transplant recipients, especially those who do not require infectious diseases consultation.

Pediatric patients who receive antibiotics for fever and neutropenia in less than 60 min have decreased intensive care needs

BACKGROUND

Antibiotic delivery to patients with fever and neutropenia (F&N) in <60 min is an increasingly important quality measure for oncology centers, but several published reports indicate that a time to antibiotic delivery (TTA) of <60 min is quite difficult to achieve. Here we report a quality improvement (QI) effort that sought to decrease TTA and assess associated clinical outcomes in pediatric patients with cancer and F&N.

PROCEDURE

We used Lean-Methodology and a Plan-Do-Study-Act approach to direct QI efforts and prospectively tracked TTA measures and associated clinical outcomes (length of stay, duration of fever, use of imaging studies to search for occult infection, bacteremia, intensive care unit (ICU) consultation or admission, and mortality). We then performed statistical analysis to determine the impact of our QI interventions on total TTA, sub-process times, and clinical outcomes.

RESULTS

Our QI interventions significantly improved TTA such that we are now able to deliver antibiotics in <60 min nearly 100% of the time. All TTA sub-process times also improved. Moreover, achieving TTA <60 min significantly reduced the need for ICU consultation or admission (P = 0.003) in this population.

CONCLUSION

Here we describe our QI effort along with a detailed assessment of several associated clinical outcomes. These data indicate that decreasing TTA to <60 min is achievable and associated with improved outcomes in pediatric patients with cancer and F&N.

Impact of infectious disease consultation on the clinical and economic outcomes of solid organ transplant recipients admitted for infectious complications

BACKGROUND

There has been a paucity of data on the healthcare resource utilization of infectious disease-related complications in solid organ transplant recipients. The aims of this study were to report the clinical and economic burden of infectious disease-related complications, along with the impact of infectious disease consultation.

METHODS

This cohort study evaluated patients requiring admission to a tertiary-care center during 2007, 2008, and 2011. Propensity score matching was used to estimate the effects of patient demographics, comorbidities, and transplant- and infection-related factors on 28-day hospital survival, length of stay (LOS), and medical costs.

RESULTS

Infectious disease-related complications occurred in 603 of 1414 (43%) admissions in 306 of 531 (58%) patients. Unadjusted 28-day mortality did not differ between those who received infectious disease consultations vs those who did not (2.9% vs 3.6%, P = .820), however, after propensity score matching, infectious disease consultation resulted in significantly greater 28-day survival estimates (hazard ratio = 0.33; log-rank P = .026), and reduced 30-day rehospitalization rates (16.9% vs 23.9%, P = .036). The median LOS and hospitalization costs were significantly increased for patients receiving an infectious disease consultation than in those managed by the attending team alone (7.0 vs 5.0 days, P = .002, and $9652 vs $6192, P = .003). However, the median LOS (5.5 vs 5.1 days, P = .31) and hospitalization costs ($8106 vs $6912, P = .63) did not differ significantly among those receiving an early infectious disease consultation (<48 hours) vs no consultation, respectively.

CONCLUSIONS

Infectious disease consultation in recipients of solid organ transplant is associated with increased LOS and hospitalization costs but decreased mortality and reduced rehospitalization rates. Early consultation with infectious disease specialists decreases healthcare resource utilization compared with delayed referrals.

[Nosocomial infection in patients receiving a solid organ transplant or haematopoietic stem cell transplant]

Bacterial infections are the most common infections in solid organ transplant recipients. These infections occur mainly in the first month after transplantation and are hospital-acquired. Nosocomial infections cause significant morbidity and are the most common cause of mortality in this early period of transplantation. These infections are caused by multi-drug resistant (MDR) microorganisms, mainly Gram-negative enterobacteria, non-fermentative Gram-negative bacilli, enterococci, and staphylococci. The patients at risk of developing nosocomial bacterial infections are those previously colonized with MDR bacteria while on the transplant waiting list. Intravascular catheters, the urinary tract, the lungs, and surgical wounds are the most frequent sources of infection. Preventive measures are the same as those applied in non-immunocompromised, hospitalized patients except in patients at high risk for developing fungal infection. These patients need antifungal therapy during their hospitalization, and for preventing some bacterial infections in the early transplant period, patients need vaccinations on the waiting list according to the current recommendations. Although morbidity and mortality related to infectious diseases have decreased during the last few years in haematopoietic stem cell transplant recipients, they are still one of the most important complications in this population. Furthermore, as occurs in the general population, the incidence of nosocomial infections has increased during the different phases of transplantation. It is difficult to establish general preventive measures in these patients, as there are many risk factors conditioning these infections. Firstly, they undergo multiple antibiotic treatments and interventions; secondly, there is a wide variability in the degree of neutropenia and immunosuppression among patients, and finally they combine hospital and home stay during the transplant process. However, some simple measures could be implemented to improve the current situation.

Cohort study of the impact of time to antibiotic administration on mortality in patients with febrile neutropenia

The time to antibiotic administration (TTA) has been proposed as a quality-of-care measure in febrile neutropenia (FN); however, few data regarding the impact of the TTA on the mortality of adult cancer patients with FN are available. The objective of this study was to determine whether the TTA is a predictor of mortality in adult cancer patients with FN. A prospective cohort study of all consecutive cases of FN, evaluated from October 2009 to August 2011, at a single tertiary referral hospital in southern Brazil was performed. The TTA was assessed as a predictive factor for mortality within 28 days of FN onset using the Cox proportional hazards model. Kaplan-Meier curves were used for an assessment of the mortality rates according to different TTAs; the log-rank test was used for between-group comparisons. In total, 307 cases of FN (169 subjects) were evaluated. During the study period, there were 29 deaths. In a Cox regression analysis, the TTA was independently associated with mortality within 28 days (hazard ratio [HR], 1.18; 95% confidence interval [CI], 1.10 to 1.26); each increase of 1 h in the TTA raised the risk of mortality within 28 days by 18%. Patients with FN episodes with a TTA of ≤ 30 min had lower 28-day mortality rates than those with a TTA of between 31 min and 60 min (3.0% versus 18.1%; log-rank P = 0.0002). Early antibiotic administration was associated with higher survival rates in the context of FN. Efforts should be made to ensure that FN patients receive effective antibiotic therapy as soon as possible. A target of 30 min to the TTA should be adopted for cancer patients with FN.

Prolonged antibiotic use induces intestinal injury in mice that is repaired after removing antibiotic pressure: implications for empiric antibiotic therapy

Metabolic profiling of urine and fecal extracts, histological investigation of intestinal ilea, and fecal metagenomics analyses were used to investigate effects of prolonged antibiotic use in mice. The study provides insight into the effects of extended empiric antibiotic therapy in humans. Mice were administered a broad-spectrum antibiotic for four consecutive days followed by oral gavage with Clostridium butyricum, an opportunistic gram-positive pathogenic bacteria commonly isolated in fecal and blood cultures of necrotizing enterocolitis patients. Metagenomics data indicated loss of bacterial diversity after 4 days on antibiotics that was restored after removing antibiotic pressure. Histological analyses indicated damage to ileal villi after antibiotic treatment that underwent repair after lifting antibiotic pressure. Metabolic profiling confirmed intestinal injury in antibiotic-treated mice indicated by increased urinary trans-4-hydroxy-l-proline, a breakdown product of collagen present in connective tissue of ileal villi that may serve as a biomarker for antibiotic-induced injury in at risk populations.

An alternate pathophysiologic paradigm of sepsis and septic shock: implications for optimizing antimicrobial therapy

The advent of modern antimicrobial therapy following the discovery of penicillin during the 1940s yielded remarkable improvements in case fatality rate of serious infections including septic shock. Since then, pathogens have continuously evolved under selective antimicrobial pressure resulting in a lack of significant improvement in clinical effectiveness in the antimicrobial therapy of septic shock despite ever more broad-spectrum and potent drugs. In addition, although substantial effort and money has been expended on the development novel non-antimicrobial therapies of sepsis in the past 30 years, clinical progress in this regard has been limited. This review explores the possibility that the current pathophysiologic paradigm of septic shock fails to appropriately consider the primacy of the microbial burden of infection as the primary driver of septic organ dysfunction. An alternate paradigm is offered that suggests that has substantial implications for optimizing antimicrobial therapy in septic shock. This model of disease progression suggests the key to significant improvement in the outcome of septic shock may lie, in great part, with improvements in delivery of existing antimicrobials and other anti-infectious strategies. Recognition of the role of delays in administration of antimicrobial therapy in the poor outcomes of septic shock is central to this effort. However, therapeutic strategies that improve the degree of antimicrobial cidality likely also have a crucial role.

Diagnostic bronchoscopy in solid-organ and hematopoietic stem cell transplantation

Fiberoptic bronchoscopy is a valuable diagnostic tool in solid-organ and hematopoietic stem cell transplant recipients presenting with a range of pulmonary complications. This article provides a comprehensive overview of the utility and potential adverse effects of diagnostic bronchoscopy for transplant recipients. Recommendations are offered on the selection of patients, the timing of bronchoscopy, and the samples to be obtained across the spectrum of suspected pulmonary complications of transplantation. Based on review of the literature, the authors recommend early diagnostic bronchoscopy over empiric treatment in transplant recipients with evidence of certain acute, subacute, or chronic pulmonary processes. This approach may be most critical when an underlying infectious etiology is suspected. In the absence of prompt diagnostic information on which to base effective treatment, the risks associated with empiric antimicrobial therapy, including medication side effects and the development of antibiotic resistance, compound the potential harm of delaying targeted management.

Prompt administration of antibiotics is associated with improved outcomes in febrile neutropenia in children with cancer

BACKGROUND

Time-to-antibiotic (TTA) administration is a widely used quality-of-care measure for children with cancer and febrile neutropenia (FN). We sought to determine whether TTA is associated with outcomes of FN.

PROCEDURE

A single-center, retrospective cohort study was conducted of 1,628 FN admissions from 653 patients from 2001 to 2009. Outcome variables included (1) an adverse event (AE) composite of in-hospital mortality, pediatric intensive care unit (PICU) admission within 24 hours of presentation, and/or fluid resuscitation ≥ 40 ml/kg within 24 hours of presentation and (2) length of stay (LOS). TTA was measured as a continuous variable and in 60-minute intervals. Mixed regression models were constructed to evaluate associations of TTA with the outcome variables after adjusting for relevant covariates including cancer diagnosis, degree of myelosuppression, and presence of bacteremia.

RESULTS

The composite AE outcome occurred in 11.1% of admissions including 0.7% in-hospital mortality, 4.7% PICU admission, and 10.1% fluid resuscitation. In univariate analysis, TTA was associated with the composite AE outcome (Odds Ratio [OR] 1.29, 95% CI 1.02-1.64) but not LOS. In multivariate analysis, after adjustment for relevant covariates, 60-minute TTA intervals were associated with the composite AE outcome (61-120 minutes vs. ≤ 60 minutes, OR 1.81, 95% CI 1.01-3.26). Unexpectedly, admission from the emergency department (ED) was also independently associated with the composite AE outcome (ED vs. clinic, OR 3.15, 95% CI 1.95-5.09).

CONCLUSIONS

TTA and presentation to the ED are independently associated with poor outcomes of FN.

Trauma after transplant: hold the antibiotics please

OBJECTIVE

Despite the increase in transplantation and the prevalence of trauma as a major disease entity, few data exist about transplant patients who suffer trauma. We conducted a study to determine whether transplant patients (TP) have worse outcomes, particularly of infections, than do their non-transplant (NTP) counterparts after trauma.

METHODS

We performed a retrospective review of trauma patients from 2006 to 2010. All patients who had undergone organ transplantation were included and compared through 1:3 propensity matching with their NTP counterparts. Data for the groups were compared to determine differences in outcomes.

RESULTS

The review included 17 TP (13 kidney, 2 liver, 1 kidney/liver, and 1 kidney/pancreas) as compared with 51 NTP. The patients were matched for injury severity score (ISS), age, and gender, with most suffering blunt trauma (82.4% [14/17] TP vs. 90% [46/51] NTP, p = 0.5). The groups had similar initial Glasgow Coma Scale (GCS) scores (13.2 ± 4.5 TP vs. 13.9 ± 2.5 NTP, p=0.6), serum lactate concentrations (2.0 ± 1.8 mmol/L TP vs. 2.3 ± 1.5 mmol/L NTP, p=0.39), and base deficits (-1.5 ± 4.0 TP vs. 0.6 ± 3.0 NTP, p=0.21). Comorbidities were more common in the TP than in the NTP group. The groups had similar lengths of stay (days on ventilator: 0.1 ± 0.3 TP vs. 0.4 ± 1.6 NTP, p=0.9; days in ICU: 0.2 ± 0.6 TP vs. 2.4 ± 5.9 NTP, p=0.16; days in hospital: 5.2 ± 6.8 TP vs. 7.5 ± 10.2 NTP, p=0.86), and two deaths occurred in each of the two groups (p=0.26). Overall complications were similar (52.94% [9/17] TP vs. 62.75% [32/51] NTP, p=0.57), and there were only two infections, both in the NTP group (p=1.0). Antibiotics were given to 59% of the TP vs. 39% of the NTP, with an average duration of 8.4 days for the TP vs. 3.9 days for the NTP.

CONCLUSION

When matched equally for degree of injury, the TP and NTP had similar outcomes. There also appeared to be no differences in infectious complications in the two groups, yet more of the TP had exposure to more days of antibiotics. Similar protocols of antimicrobial therapy should apply to both TP and NTP to avoid the overuse of antimicrobial agents and ensure maintenance of the susceptibility patterns of pathogens.

Multidrug-resistant bacterial infection in solid organ transplant recipients

The most frequent complication from infection after solid organ transplantation is bacterial infection. This complication is more frequent in organ transplantation involving the abdominal cavity, such as liver or pancreas transplantation, and less frequent in heart transplant recipients. The sources, clinical characteristics, antibiotic resistance and clinical outcomes vary according to the time of onset after transplantation. Most bacterial infections during the first month post-transplantation are hospital acquired, and there is usually a high incidence of multidrug-resistant bacterial infections. The higher incidence of complications from bacterial infection in the first month post-transplantation may be associated with high morbidity. Of special interest due to their frequency are infections by S. aureus, enterococci, Gram-negative enteric and non-fermentative bacilli. Opportunistic bacterial infections may occur at any time on the posttransplant timeline, but are more frequent between months two and six, the period in which immunosuppression is higher. The most frequent bacterial species causing opportunistic infections in organ transplant recipients are Listeria monocytogenes and Nocardia spp. After month six, posttransplantation solid organ transplant patients usually develop conventional community-acquired bacterial infections, especially urinary tract infections by E. coli and S. pneumoniae pneumonia. In this article we review the clinical characteristics, epidemiology, diagnosis and prognosis of bacterial infections in solid organ transplant patients.

The preanalytical optimization of blood cultures: a review and the clinical importance of benchmarking in 5 Belgian hospitals

Bloodstream infections remain a major challenge in medicine. Optimal detection of pathogens is only possible if the quality of preanalytical factors is thoroughly controlled. Since the laboratory is responsible for this preanalytical phase, the quality control of critical factors should be integrated in its quality control program. The numerous recommendations regarding blood culture collection contain controversies. Only an unambiguous guideline permits standardization and interlaboratory quality control. We present an evidence-based concise guideline of critical preanalytical determinants for blood culture collection and summarize key performance indicators with their concomitant target values. In an attempt to benchmark, we compared the true-positive rate, contamination rate, and collected blood volume of blood culture bottles in 5 Belgian hospital laboratories. The true-positive blood culture rate fell within previously defined acceptation criteria by Baron et al. (2005) in all 5 hospitals, whereas the contamination rate exceeded the target value in 4 locations. Most unexpected, in each of the 5 laboratories, more than one third of the blood culture bottles were incorrectly filled, irrespective of the manufacturer of the blood culture vials. As a consequence of this shortcoming, one manufacturer recently developed an automatic blood volume monitoring system. In conclusion, clear recommendations for standardized blood culture collection combined with quality control of critical factors of the preanalytical phase are essential for diagnostic blood culture improvement.

Staphylococcus aureus bacteremia in solid organ transplant recipients: evidence for improved survival when compared with nontransplant patients

BACKGROUND

Staphylococcus aureus bacteremia (SAB) is an important cause of morbidity and mortality. Herein, we describe the incidence, clinical characteristics, and outcomes of SAB after solid organ transplantation (SOT) and compare these features with non-SOT controls.

METHODS

In a single-center retrospective study, blood cultures positive for S. aureus were obtained from January 1, 2000, to December 31, 2008. Chart review was performed on all SOT recipients with SAB. The social security death index was used to determine all-cause mortality.

RESULTS

Seventy of 2959 patients with SAB were SOT recipients (26 lung, 19 liver, 18 kidney, and seven heart). The overall attack rate of SAB in SOT was 22.9/1000 transplant patients. Early-onset SAB (≤ 90 days) was more frequent in liver recipients (79%), when compared with kidney recipients (17%). All-cause 30-day and 1-year mortality rates were 6% and 28% in SOT, respectively. Pneumonia as a source was associated with an increased 30-day mortality (18% vs. 2%, P = 0.04). Comparing SOT versus non-SOT controls, methicillin resistance was more frequent (86% vs. 52%, P < 0.0001), and duration of bacteremia was longer (mean 3.8 vs. 1.6 days, P < 0.01). SOT status was independently associated with lower risk of 30-day mortality (risk ratio [RR]: 0.37, P = 0.02).

CONCLUSIONS

In our cohort of SOT recipients, SAB was less common than previously reported and surprisingly had lower 30-day mortality, when compared with non-SOT. In SOT recipients, pneumonia as a source of SAB in SOT is associated with an increased 30-day mortality.

Time-to-antibiotic administration as a quality of care measure in children with febrile neutropenia: a survey of pediatric oncology centers

Time-to-antibiotic administration (TTA) has been suggested as a quality-of-care (QOC) measure for pediatric oncology patients with febrile neutropenia (FN). Unknown, however, is to what extent pediatric oncology centers utilize TTA. Therefore, we designed and administered an electronic survey (68% response rate) of programs in the Children's Oncology Group to assess TTA utilization. Nearly half of respondents track TTA. Most reported using a benchmark of less than 60 min from arrival. TTA is a commonly used QOC measure for pediatric FN despite an absence of studies establishing its validity and a lack of data supporting its impact on outcomes of FN.

Infectious complications more than 1 year after liver transplantation: a 3-decade nationwide experience

Because few reports have addressed infections late (≥1 year) after liver transplantation (LT), we evaluated the incidence, risk factors and pathogens involved. Infection data were from the Finnish LT registry, with starting date, type and relevant pathogens for 501 Finnish adult LT patients surviving ≥1 year post-transplant. Follow-up end points were end of study, death or retransplantation. Logistic regression to assess risk factors was adjusted for age, gender and follow-up time. With 3923 person-years of follow-up, overall infection incidence was 66/1000 person-years; 155 (31%) suffered 259 infections, and two-thirds experienced only one infection. Cholangitis (20%), pneumonia (19%) and sepsis (14%) were most common. The most frequent bacteria were Enterococcus spp. and Escherichia coli, and the most frequent viruses cytomegalovirus and varicella zoster virus. Fungal infections were rare (n = 7). With 13 fatal infections, 17% of all late deaths involved infection. Primary sclerosing cholangitis (PSC) and Roux-en-Y-type biliary anastomosis were associated with cholangitis; 18% of PSC patients suffered late cholangitis. Late acute rejection was associated with sepsis. Age, gender or cytomegalovirus did not significantly influence late infections. In conclusion, although infection risk under maintenance immunosuppression therapy is relatively low, particular vigilance regarding cholangitis, pneumonia and sepsis seems appropriate.